Exam 2: Life, Chemistry, and Water

Figure 2.4 The water strider shown in the figure above is able to stand on water because of the ____ of water.

Ice floats in liquid water because there are, on average, fewer hydrogen bonds between molecules in ice than water, resulting in a lower density.

Which element is likely to be chemically unreactive?

Ethanol, the alcohol found in wine and beer, has the molecular formula CH₃CH₂OH. What is the molecular weight of ethanol if the atomic weight of C=12, H=1, and O=16?

In water, NaOH almost completely separates into Na⁺and OH^-ions. Thus, NaOH is _____.

Figure 2.1 -Answer the question using the accompanying figure. The atomic number of the atom depicted in the figure is ____.

When salt dissolves in water, the water molecules form ____ around the Na⁺and Cl^-ions.

The formation and breaking of bonds between atoms requires ____.

Diluted acetic acid, CH₃COOH, is commonly called vinegar. How many atoms of hydrogen are present in one molecule of acetic acid?

Acid precipitation can have a pH as low as 3.

The polarity of water allows it to create a hydration layer that prevents salt from coming back out of solution after it has been dissolved.

Which substance would have the most difficulty entering a water lattice?

How many calories, as defined in chemistry, are in one calorie, which is the unit used to quantify the amount of energy in the food we eat?

Which element is most likely to share electrons with other atoms in joint orbitals?

Geckos are able to cling to vertical walls due to ____.

A ____ is formed when a ____ is dissolved in a ____.

Why is iodine considered a trace element, and what is its biological function in humans?

Hydrogen, atomic number 1, has three isotopes,¹H,²H,³H.¹H is comprised of one proton, one neutron, and one electron.

Figure 2.2 - Answer the question using the accompanying figure. All of the orbitals shown in the neon atom are completely filled with electrons. How many electrons does this neon atom have?